Production and Characterization of Bacterial Cellulose Separators for Nickel-Zinc Batteries

The need for energy-storing technologies with lower environmental impact than Li-ion batteries but similar power metrics has revived research in Zn-based battery chemistries. application of bio-based materials as a replacement current components can additionally contribute to an improved sustainability Zn systems. For that reason, bacterial cellulose (BC) was investigated separator material Ni-Zn batteries. Following the biotechnological production BC, biopolymer purified, and differently shaped separators were generated while surveying alterations its crystalline structure via X-ray diffraction measurements during whole manufacturing process. A decrease crystallinity partial change BC crystal allomorph type Iα II determined upon soaking electrolyte. Electrolyte uptake found be accompanied by dimensional shrinkage swelling, which associated decrystallization hydration amorphous content. selectivity hydroxide zincate ions higher BC-based compared commercial glass-fiber (GF) or polyolefin estimated from obtained diffusion coefficients. Electrochemical cycling showed good C-rate capability cells based on GF separators, whereas cell aging pronounced both cases due migration anode passivation. Lower electrolyte retention concluded major reason faster capacity fading supersaturation within separator. However, combining dense low permeability porous one reservoir reduced ZnO accumulation stability, hence showing potentials adjustment.